1. Field of the Invention
The invention relates to filtering systems for use with food fryers and particularly to a system which continuously filters and purifies the cooking oil, even when the fryer is in use and when the oil is heated. More particularly, the invention relates to a continuous cooking oil filtering system having a unique chopper pump which comminutes the food particles contained in the oil whereby the particles can be removed easily from the oil by filtering before the oil is returned into the fryer.
2. Description of the Prior Art
Restaurants and other establishments in which food is prepared use fryers for the preparation of many foods. These fryers contain a quantity of cooking oil in a frying well which is heated to a predetermined temperature such as 325.degree. F. for the preparation of food such as chicken, potatoes, onions and fish. Many of these foods are covered with flour or dough before immersion in the cooking oil. Although these fryers cook the food satisfactorily, problems are encountered in that an appreciable amount of food particles accumulate in the oil. These food particles will affect the flavor of the foods being cooked in a relatively short period of time, especially where different foods are cooked in the same oil which requires frequent cleaning and/or replacement of the cooking oil.
In many food establishments, the cooking oil is removed from the frying well at the end of each day and passed through a mesh cloth or other filter and into a second vessel, whereupon it is poured back into the frying well. This procedure must be accomplished when the fryer is inoperative and removed from service and the cooking oil has cooled to a safe temperature for handling by the restaurant personnel. Even if cleaned at the end of each day, the cooking oil ordinarily must be disposed of after several days of use. This requires an additional cost to the restaurant owner due to the considerable amount of cooking oil required. For example, many usual fryers will contain approximately thirty or forty pounds of cooking oil. Furthermore, the manual filtering of the cooking oil requires a considerable amount of manpower and "down time" of the fryers from service.
A solution to this problem has been attempted by several systems which continuously filter and recycle the cooking oil, such as shown in U.S. Pat. Nos. 3,280,722, 3,685,433, 3,968,741 and 3,977,973.
These prior art filtering systems usually are complicated, expensive, and occupy an excessive amount of space. Also many of these systems are not adaptable to existing food fryers, and more importantly are highly susceptible to clogging requiring frequent changing of the filters due to the size of the food particles. Also, such systems must be removed from service or rendered inoperative while changing of the filters takes place.
There is no known continuous filtering system for cooking oil of which I am aware which eliminates these problems in a relatively simple, rugged and efficient arrangement of components as in my system.